AL-6XN Plus is an enhanced variant of AL-6XN, the 6-Mo superaustenitic stainless developed by Allegheny Technologies. It carries the same core alloying strategy — high nickel, high chromium, and roughly 6-7% molybdenum — but with nickel, chromium, and molybdenum all nudged slightly higher than standard AL-6XN. That extra alloy margin is intended to push pitting and crevice corrosion resistance a step further for the most aggressive chloride service, while retaining the fully austenitic, non-magnetic structure and general processing characteristics of the AL-6XN family.

Like standard AL-6XN, AL-6XN Plus is aimed at seawater and brine handling, offshore and marine hardware, and chemical processing equipment exposed to chlorides or other halides where 316 stainless would pit prematurely. It is fully austenitic and cannot be strengthened by heat treatment; strength increases only through cold work.

AL-6XN Plus is a proprietary enhanced variant marketed within the AL-6XN (UNS N08367) family. A distinct standalone UNS number specific to the "Plus" chemistry could not be independently verified, so it is not listed separately here.

Composition is slightly richer in Ni, Cr, and Mo than standard AL-6XN, consistent with its role as an enhanced-corrosion-resistance variant of the same base alloy.

AL-6XN Plus machines much like standard AL-6XN, only slightly more demanding given its incrementally higher nickel, chromium, and molybdenum content. It is a soft, ductile, fully austenitic matrix that resists shearing cleanly and work-hardens quickly wherever the tool rubs instead of cutting — the same gummy behavior seen across the high-alloy austenitic and superaustenitic family, just with a bit more alloy content driving cutting forces and abrasive wear higher.

As with AL-6XN, a sharp positive-rake insert with a stainless-specific chipbreaker is essential to keep the chip shearing away cleanly rather than dragging and work-hardening the surface. Firm, consistent feeds that cut beneath any hardened skin from the previous pass matter more here than trying to finesse a light cut. Low thermal conductivity concentrates heat at the cutting edge, so coolant and a wear-resistant coated grade help offset the abrasive wear from the elevated Ni-Cr-Mo content. Rigid workholding and short tool overhang pay off more on this alloy than on lower-alloy stainless.

Values assume favorable conditions: a well-matched insert grade, rigid tool and workpiece clamping, good raw material quality, short tool overhang, and adequate coolant. Run toward the lower end of each range given the alloy's high Ni-Cr-Mo content.

Turning

Parting / Grooving

Milling